Protein Kinase D was involved in vascular remodeling in spontaneously hypertensive rats.

The present study was designed to determine the role of PKD in vascular remodeling (VR) in Spontaneously hypertensive rats (SHRs). Increased SBP, VR and PKD activation were prominent in SHRs. The SBP has a positive correlation with the activation of PKD in SHRs. The ratio of media to lumen (MT/LD), volume fraction of collagen (VFC), hydroxyproline, IL-6, TNF-α and nitrotyrosine content were significantly related to the activated PKD. It may be concluded that PKD plays a central role in VR, and the mechanism may be related to its regulation of hypertrophy, fibrosis, inflammation and oxidative stress.

BRD7 mediates hyperglycaemia-induced myocardial apoptosis via endoplasmic reticulum stress signalling pathway.

Bromodomain-containing protein 7 (BRD7) is a tumour suppressor that is known to regulate many pathological processes including cell growth, apoptosis and cell cycle. Endoplasmic reticulum (ER) stress-induced apoptosis plays a key role in diabetic cardiomyopathy (DCM). However, the molecular mechanism of hyperglycaemia-induced myocardial apoptosis is still unclear. We intended to determine the role of BRD7 in high glucose (HG)-induced apoptosis of cardiomyocytes. In vivo, we established a type 1 diabetic rat model by injecting a high-dose streptozotocin (STZ), and lentivirus-mediated short hairpin RNA (shRNA) was used to inhibit BRD7 expression. Rats with DCM exhibited severe myocardial remodelling, fibrosis, left ventricular dysfunction and myocardial apoptosis. The expression of BRD7 was up-regulated in the heart of diabetic rats, and inhibition of BRD7 had beneficial effects against diabetes-induced heart damage. In vitro, H9c2 cardiomyoblasts was used to investigate the mechanism of BRD7 in HG-induced apoptosis. Treating H9c2 cardiomyoblasts with HG elevated the level of BRD7 via activation of extracellular signal-regulated kinase 1/2 (ERK1/2) and increased ER stress-induced apoptosis by detecting spliced/active X-box binding protein 1 (XBP-1s) and C/EBP homologous protein (CHOP). Furthermore, down-regulation of BRD7 attenuated HG-induced expression of CHOP via inhibiting nuclear translocation of XBP-1s without affecting the total expression of XBP-1s. In conclusion, inhibition of BRD7 appeared to protect against hyperglycaemia-induced cardiomyocyte apoptosis by inhibiting ER stress signalling pathway.

Irbesartan ameliorates diabetic cardiomyopathy by regulating protein kinase D and ER stress activation in a type 2 diabetes rat model.

Recent studies demonstrate an important role of protein kinase D (PKD) in the cardiovascular system. However, the potential role of PKD in the pathogenesis of diabetic cardiomyopathy (DCM) remains unclear. Irbesartan has beneficial effects against diabetes-induced heart damage, while the mechanisms were still poorly understood. Our present study was designed to investigate the effects of irbesartan in DCM and whether the cardioprotective effects of irbesartan were mediated by PKD and endoplasmic reticulum (ER) stress. We induced the type 2 diabetic rat model by high fat diet and low dose streptozotocin injection. The characteristics of type 2 DCM were evaluated by metabolic tests, echocardiography and histopathology. 8-weeks administration of irbesartan (15, 30 and 45mg/kg/day) was used to evaluate the effect irbesartan in DCM. Diabetic rats revealed severe metabolic abnormalities, left ventricular dysfunction, myocardial fibrosis and apoptosis. PKD and ER stress were excessive activated in the myocardium of diabetic rats. Furthermore, cardiac fibrosis, apoptosis, diastolic dysfunction and ER stress were all significantly related to PKD activation in diabetic rats. Irbesartan treatment attenuated the activation of PKD and ER stress, which paralleled its cardioprotective effects. Our study suggests that irbesartan could ameliorate cardiac remodeling and dysfunction in type 2 diabetes, and these beneficial effects were associated with its ability to suppress the activation of PKD and ER stress.

SDF-1/CXCR4 axis promotes directional migration of colorectal cancer cells through upregulation of integrin αvß6.

Colorectal cancer (CRC) displays a predilection for metastasis to liver. Although stromal cell-derived factor-1 (SDF-1)/CXCR4 plays an important role in the liver metastasis, the molecular mechanism still remains obscure. We previously reported that integrin αvß6 was implicated in the progression of CRC. However, no data are currently available on the cross talk between CXCR4 and αvß6. In the present study, we first demonstrated the cross talk between CXCR4 and αvß6 and their role in liver metastasis of CRC. We analyzed 159 human CRC samples and found that expression of CXCR4 and αvß6 was significantly associated with liver metastasis, and interestingly expression of αvß6 significantly correlated with expression of CXCR4. Both CXCR4 and αvß6 were highly expressed in metastatic CRC cell lines HT-29 and WiDr, whereas both of them were exiguous in non-metastatic cell line Caco-2. Furthermore, inhibition of αvß6 significantly decreased SDF-1α-induced cell migration in vitro. SDF-1/CXCR4 could upregulate αvß6 expression through phosphorylation of ERK and activation of Ets-1 transcription factor. In conclusion, we demonstrate that SDF-1/CXCR4 induces directional migration and liver metastasis of CRC cells by upregulating αvß6 through ERK/Ets-1 pathway. These data support combined inhibition of CXCR4 and αvß6 to prevent development of liver metastasis of CRC.

HMGB1 mediates hyperglycaemia-induced cardiomyocyte apoptosis via ERK/Ets-1 signalling pathway.

Apoptosis is a key event involved in diabetic cardiomyopathy. The expression of high mobility group box 1 protein (HMGB1) is up-regulated in diabetic mice. However, the molecular mechanism of high glucose (HG)-induced cardiomyocyte apoptosis remains obscure. We aimed to determine the role of HMGB1 in HG-induced apoptosis of cardiomyocytes. Treating neonatal primary cardiomyocytes with HG increased cell apoptosis, which was accompanied by elevated levels of HMGB1. Inhibition of HMGB1 by short-hairpin RNA significantly decreased HG-induced cell apoptosis by reducing caspase-3 activation and ratio of Bcl2-associated X protein to B-cell lymphoma/leukemia-2 (bax/bcl-2). Furthermore, HG activated E26 transformation-specific sequence-1 (Ets-1), and HMGB1 inhibition attenuated HG-induced activation of Ets-1 via extracellular signal-regulated kinase 1/2 (ERK1/2) signalling. In addition, inhibition of Ets-1 significantly decreased HG-induced cardiomyocyte apoptosis. Similar results were observed in streptozotocin-treated diabetic mice. Inhibition of HMGB1 by short-hairpin RNA markedly decreased myocardial cell apoptosis and activation of ERK and Ets-1 in diabetic mice. In conclusion, inhibition of HMGB1 may protect against hyperglycaemia-induced cardiomyocyte apoptosis by down-regulating ERK-dependent activation of Ets-1.

Rosuvastatin alleviates diabetic cardiomyopathy by inhibiting NLRP3 inflammasome and MAPK pathways in a type 2 diabetes rat model.

PURPOSE: Nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome is important in inflammation of several diabetic complications. However, the potential role of NLRP3 inflammasome in the inflammatory process of diabetic cardiomyopathy (DCM) remains unclear. Although rosuvastatin (RSV) has an anti-inflammatory effect on some cardiovascular diseases, its influence on DCM is incompletely understood. We aimed to explore the effect on and underlying mechanism of RSV in DCM, and whether NLRP3 is a target for RSV. METHODS: Type 2 diabetes was induced in rat. The characteristics of type 2 DCM were evaluated by metabolic tests, echocardiography and histopathology. The expression of factors was determined by real-time RT-PCR and western blot. Eight-week RSV treatment and NLRP3 gene silencing were used to investigate the effect and underlying target of RSV in DCM. RESULTS: Compared with controls, diabetic rats showed severe metabolic disorder, cardiac dysfunction, fibrosis, disorganized ultrastructure, and excessive activation of thioredoxin interacting/inhibiting protein (TXNIP, p < 0.05), NLRP3 inflammasome (NLRP3, p < 0.01; apoptosis-associated speck-like protein containing a caspase recruitment domain [ASC], p < 0.05; caspase-1, p < 0.01), interleukin-1ß (p < 0.01) and mitogen-activated protein kinases (MAPKs, all p < 0.01). Compared with diabetes alone, RSV ameliorated the overexpression of NLRP3 inflammasome (NLRP3, p < 0.05; ASC, p < 0.05; pro-caspase-1 p < 0.05, caspase-1 p20, p < 0.01) and MAPKs (all p < 0.05), which paralleled the cardiac protection of RSV. Silencing NLRP3 ameliorated cardiac remodeling and dysfunction. The beneficial effects of RSV in vehicle-treated rats were all abrogated in NLRP3-silenced rats. CONCLUSIONS: The beneficial effect of RSV on DCM depended on inhibited NLRP3 inflammasome, and correlated with suppression of the MAPKs.

Butylphthalide combined with donepezil for the treatment of vascular dementia: a meta-analysis.

OBJECTIVE: To systematically evaluate the efficacy and safety of butylphthalide combined with donepezil versus butylphthalide monotherapy for the treatment of vascular dementia. METHODS: Randomized controlled trials were searched in electronic databases, including PubMed, Embase, the Cochrane Library, China National Knowledge Infrastructure, Chinese Science and Technology Periodical Database (VIP), Wan Fang, and China Biology Medicine from inception to 29 November 2022. Two reviewers independently screened the papers and extracted data from the included studies. The data were processed using RevMan5.4 statistical software. RESULTS: Nine randomized controlled trials (n = 1024) were included in this meta-analysis. Regarding the primary outcomes, compared with butylphthalide monotherapy, combined butylphthalide and donepezil treatment exhibited significantly greater total clinical efficacy (relative risk = 1.24, 95% confidence interval [1.17, 1.31]) and did not increase the adverse event rate (relative risk = 1.39, 95% confidence interval [0.91, 2.14]). Regarding the secondary outcomes, the meta-analysis results for the Mini-Mental State Examination, abilities of daily living, and Montreal Cognitive Assessment scores and the interleukin-6, tumor necrosis factor-α, and superoxide dismutase blood levels all supported combined butylphthalide and donepezil treatment. CONCLUSION: Butylphthalide combined with donepezil may be a better treatment strategy than donepezil alone for the treatment of vascular dementia in clinical practice.

Case Report: Hypereosinophilic syndrome vs. patent foramen ovale as etiopathogenetic contributors to stroke.

Hypereosinophilic syndrome (HES), characterized by an increased number of eosinophils in tissues and/or blood, presents with heterogeneous clinical manifestations. Studies have shown that HES can affect the nervous system and may be associated with cerebral infarction. Patent foramen ovale (PFO) is the most common congenital intracardiac defect that can cause right-to-left shunting and contribute to the paradoxical embolization of venous emboli, and even lead to stroke. We report the case of a young man who presented with cerebral infarction accompanied by both HES and PFO. The patient underwent thorough evaluation to determine the source of emboli and the potential pathogenesis. In this case, HES was confirmed and glucocorticoid treatment was conducted. Direct imaging using optical coherence tomography (OCT) confirmed that the embolus originated from the PFO. Therefore, we performed PFO occlusion. The patient recovered well, and no new cerebral infarction was observed at 6-month follow-up. Based on the results of our study, we conclude that it is important to consider unusual etiologies of cerebral infarction, particularly in younger patients.

New insights into the cortex-to-stele ratio show it to effectively indicate inter- and intraspecific function in the absorptive roots of temperate trees.

The cortex-to-stele ratio (CSR), as it increases from thin- to thick-root species in angiosperms, is theorised to effectively reflect a compensation for the 'lag' of absorption behind transportation. But it is still not known if this compensatory effect exists in gymnosperm species or governs root structure and function within species. Here, anatomical, morphological, and tissue chemical traits of absorptive roots were measured in three temperate angiosperm and three gymnosperm species. Differences in the CSR and the above functional traits, as well as their intraspecific associations, were analyzed and then compared between angiosperms and gymnosperms. At the intraspecific level, the CSR decreased with increasing root order for all species. The expected functional indication of the CSR was consistent with decreases in specific root length (SRL) and N concentration and increases in the C to N ratio (C:N ratio) and the number of and total cross-sectional area of conduits with increasing root order, demonstrating that the CSR indicates the strength of absorption and transportation at the intraspecific level, but intraspecific changes are due to root development rather than the compensatory effect. These trends resulted in significant intraspecific associations between the CSR and SRL (R 2 = 0.36 ~ 0.80), N concentration (R 2 = 0.48 ~ 0.93), the C:N ratio (R 2 = 0.47 ~ 0.91), and the number of (R 2 = 0.21 ~ 0.78) and total cross-sectional area (R 2 = 0.29 ~ 0.72) of conduits in each species (p< 0.05). The overall mean CSR of absorptive roots in angiosperms was four times greater than in gymnosperms, and in angiosperms, the CSR was significantly higher in thick- than in thin-rooted species, whereas in gymnosperms, the interspecific differences were not significant (p > 0.05). This suggests that the compensation for the lag of absorption via cortex thickness regulation was stronger in three angiosperm species than in three gymnosperm species. In addition, there was poor concordance between angiosperms and gymnosperms in the relationships between CSRs and anatomical, morphological, and tissue chemical traits. However, these gymnosperm species show a more stable intraspecific functional association compared to three angiosperm species. In general, absorptive root CSRs could manifest complex strategies in resource acquisition for trees at both intra- and interspecific levels.

[Regulation of p14(ARF) expression and induction of cell apoptosis with c-myc in a p53-independent pathway].

OBJECTIVE: To explore the regulation of p14(ARF) expression and induction of cell apoptosis with the mutant and wild-type c-myc genes in a p53-independent pathway of signal transduction. METHODS: The mutant and wild-type c-myc genes were transfected by lentivirus into HCC1937 to form the stable over-expression cell lines. Uninfected cells and lentivirus-infected ones carrying no c-myc gene acted as blank and infection controls respectively. And c-myc and p14(ARF) mRNA and protein, proliferation and apoptosis in HCC1937 with mutant and wild-type c-myc were detected by reverse transcription (RT)-PCR, Western blotting, thiazolyl blue tetrazolium bromide (MTT) and terminal deoxynucleotidyl transferase mediated X-dUTP nick end labeling (TUNEL) respectively. RESULTS: After the lentivirus-mediated gene transfer, c-myc mRNA and protein expression increased in the mutant and wild-type groups. p14(ARF) mRNA and protein increased in the wild-type group and the mutant group and there were significant difference between them with blank and infection controls (mutant groups: 0.560 ± 0.010, 0.154 ± 0.011, wild-type groups: 0.651 ± 0.010, 0.382 ± 0.013, both P < 0.05). The group of mutant and wild-type c-myc could promote the proliferation of cell growth. And c-myc was more effective to induce apoptosis in the wild-type group as compared with the mutant group (7.1% ± 0.7% vs 3.2% ± 0.4%, P < 0.05). CONCLUSIONS: In a p53-independent pathway, the over-expression of wild-type c-myc obviously up-regulates the expression of p14(ARF). And cell apoptosis may be induced through the regulation of p14(ARF)-related gene, keep balance of proliferative promotion and apoptosis induction. When there is a loss-of-function of mutant c-myc, tumorigenicity increases via a disturbed balance of proliferative promotion and apoptosis induction.

miR­132 inhibits high glucose­induced vascular smooth muscle cell proliferation and migration by targeting E2F5.

The dysregulated behavior of vascular smooth muscle cells (VSMCs) serves an important role in the pathogenesis of cardiovascular diseases in diabetes. The present study aimed to investigate the effects of microRNA (miR)­132 on the proliferation and migration of VSMCs under high glucose conditions to mimic diabetes. We observed that the expression of miR­132 was significantly decreased and that of E2F transcription factor 5 (E2F5) was upregulated in high glucose (HG)­treated VSMCs or those obtained from diabetic rats. A dual luciferase reporter gene assay revealed that miR­132 could specifically bind to the 3'­untranslated region of E2F5 and significantly suppress the luciferase activity. The proliferation and migration of diabetic rat or HG­treated VSMCs were increased compared with non­diabetic rat VSMCs and those under normal glucose conditions. Upregulation of miR­132 significantly inhibited the proliferation and migration of diabetic rat VSMCs; similar effects were observed following E2F5 downregulation. The inhibitory effects of miR­132 on the proliferation and migration of HG­treated VSMCs could be reversed by E2F5 overexpression. In conclusion, miR­132 was proposed to inhibit the proliferation and migration of diabetic rat or high­glucose­treated VSMCs by targeting E2F5. The findings of the present study suggested that increasing the expression of miR­132 may serve as a novel therapeutic approach to inhibit the progression of cardiovascular disease in diabetes.

PKD knockdown inhibits pressure overload-induced cardiac hypertrophy by promoting autophagy via AKT/mTOR pathway.

Growing evidence shows that protein kinase D (PKD) plays an important role in the development of pressure overload-induced cardiac hypertrophy. However, the mechanisms involved are not clear. This study tested our hypothesis that PKD might mediate cardiac hypertrophy by negatively regulating autophagy using the technique of PKD knockdown by siRNA. Cardiac hypertrophy was induced in 8-week old male C57BL/6 mice by transverse aortic constriction (TAC). TAC mice were then divided into five groups receiving the treatments of vehicle (DMSO), an autophagy inducer rapamycin (1 mg/kg/day, i.p.), control siRNA, lentiviral PKD siRNA (2×108 transducing units/0.1 ml, i.v. injection in one day after surgery, and repeated in 2 weeks after surgery), and PKD siRNA plus 3-methyladenine (3-MA, an autophagy inhibitor, 20 mg/kg/day, i.p.), respectively. Four weeks after TAC surgery, echocardiographic study, hematoxylin and eosin (HE) staining, and Masson's staining showed mice with TAC had significantly hypertrophy and remodeling compared with sham animals. Treatments with PKD siRNA or rapamycin significantly ameliorated the cardiac hypertrophy and dysfunction. Moreover, PKD siRNA increased cardiac autophagic activity determined by electron micrographic study and the biomarkers by Western blot, accompanied with the downregulated AKT/mTOR/S6K signaling pathway. All the cardiac effects of PDK knockdown were inhibited by co-treatment with 3-MA. These results suggest that PKD is involved in the development of cardiac hypertrophy by inhibiting cardiac autophagy via AKT/mTOR pathway.

Efficacy of Enhanced External Counterpulsation in Patients With Chronic Refractory Angina on Canadian Cardiovascular Society (CCS) Angina Class: An Updated Meta-Analysis.

A growing number of patients with chronic artery disease suffer from angina, despite the optimal medical management (ie, ß-blockers, calcium channel blockers, and long-acting nitrates) and revascularization. Currently, enhanced external counterpulsation (EECP) therapy has been verified as a noninvasive, safe therapy for refractory angina. The study was designed to evaluate the efficacy of EECP in patients with chronic refractory angina according to Canadian Cardiovascular Society (CCS) angina class.We identified systematic literature through MEDLINE, EMBASE, the Cochrane Clinical Trials Register Database, and the ClinicalTrials. gov Website from 1990 to 2015. Studies were considered eligible if they were prospective and reported data on CCS class before and after EECP treatment. Meta-analysis was performed to assess the efficacy of EECP therapy by at least 1 CCS angina class improvement, and proportion along with the 95% confidence interval (CI) was calculated. Statistical heterogeneity was calculated by I statistic and the Q statistic. Sensitivity analysis was addressed to test the influence of trials on the overall pooled results. Subgroup analysis was applied to explore potential reasons for heterogeneity.Eighteen studies were enrolled in our meta-analysis. Pooled analysis showed 85% of patients underwent EECP had a reduction by at least one CCS class (95%CI 0.81-0.88, I = 58.5%, P < 0.001). The proportion of patients enrolled at primarily different studies with chronic heart failure (CHF) improved by at least 1 CCS class was about 84% after EECP (95%CI 0.81-0.88, I = 32.7%, P = 0.1668). After 3 large studies were excluded, the pooled proportion was 82% (95%CI 0.79-0.86, I = 18%, P = 0.2528). Funnel plot indicated that some asymmetry while the Begg and Egger bias statistic showed no publication bias (P = 0.1495 and 0.2859, respectively).Our study confirmed that EECP provided an effective treatment for patients who were unresponsive to medical management and/or invasive therapy. However, the long-term benefits of EECP therapy needed further studies to evaluate in the management of chronic refractory angina.

NLRP3 gene silencing ameliorates diabetic cardiomyopathy in a type 2 diabetes rat model.

BACKGROUND: Nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome is associated with metabolic disorder and cell death, which are important triggers in diabetic cardiomyopathy (DCM). We aimed to explore whether NLRP3 inflammasome activation contributes to DCM and the mechanism involved. METHODS: Type 2 diabetic rat model was induced by high fat diet and low dose streptozotocin. The characteristics of type 2 DCM were evaluated by metabolic tests, echocardiography and histopathology. Gene silencing therapy was used to investigate the role of NLRP3 in the pathogenesis of DCM. High glucose treated H9c2 cardiomyocytes were used to determine the mechanism by which NLRP3 modulated the DCM. The cell death in vitro was detected by TUNEL and EthD-III staining. TXNIP-siRNA and pharmacological inhibitors of ROS and NF-kB were used to explore the mechanism of NLRP3 inflammasome activation. RESULTS: Diabetic rats showed severe metabolic disorder, cardiac inflammation, cell death, disorganized ultrastructure, fibrosis and excessive activation of NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), pro-caspase-1, activated caspase-1 and mature interleukin-1ß (IL-1ß). Evidence for pyroptosis was found in vivo, and the caspase-1 dependent pyroptosis was found in vitro. Silencing of NLRP3 in vivo did not attenuate systemic metabolic disturbances. However, NLRP3 gene silencing therapy ameliorated cardiac inflammation, pyroptosis, fibrosis and cardiac function. Silencing of NLRP3 in H9c2 cardiomyocytes suppressed pyroptosis under high glucose. ROS inhibition markedly decreased nuclear factor-kB (NF-kB) phosphorylation, thioredoxin interacting/inhibiting protein (TXNIP), NLRP3 inflammasome, and mature IL-1ß in high glucose treated H9c2 cells. Inhibition of NF-kB reduced the activation of NLRP3 inflammasome. TXNIP-siRNA decreased the activation of caspase-1 and IL-1ß. CONCLUSION: NLRP3 inflammasome contributed to the development of DCM. NF-κB and TXNIP mediated the ROS-induced caspase-1 and IL-1ß activation, which are the effectors of NLRP3 inflammasome. NLRP3 gene silencing may exert a protective effect on DCM.

Inhibition of high-mobility group box 1 improves myocardial fibrosis and dysfunction in diabetic cardiomyopathy.

BACKGROUND: High-mobility group box 1 (HMGB1) is an important mediator of the inflammatory response. Its expression is increased in diabetic cardiomyopathy (DCM), but its role is unclear. We investigated the potential role and mechanism of HMGB1 in diabetes-induced myocardial fibrosis and dysfunction in mice. METHODS: In vivo, type 1 diabetes was induced by streptozotocin (STZ) in mice. HMGB1 expression was knocked down by lentivirus-mediated short-hairpin RNA (shRNA). Cardiac function was assessed by echocardiography. Total collagen deposition was assessed by Masson's trichrome and Picrosirius red staining. HMGB1, collagen I and III, and transforming growth factor ß1 (TGF-ß1) expression was quantified by immunostaining and western bolt analysis. In vitro, isolated neonatal cardiac fibroblasts were treated with high glucose (HG) or recombinant HMGB1 (rHMGB1). Pharmacologic (neutralizing anti-HMGB1 antibody) or genetic (shRNA-HMGB1) inhibition of HMGB1 was used to investigate the role of HMGB1 in HG-induced functional changes of cardiac fibroblasts. RESULTS: In vivo, HMGB1 was diffusely expressed in the myocardium of diabetic mice. HMGB1 silencing ameliorated left ventricular dysfunction and remodeling and decreased collagen deposition in diabetic mice. In vitro, HG induced HMGB1 translocation and secretion in both viable cardiomyocytes and fibroblasts. Administration of rHMGB1 dose-dependently increased the expression of collagens I and III and TGF-ß1 in cardiac fibroblasts. HMGB1 inhibition reduced HG-induced collagen production, matrix metalloproteinase (MMP) activities, proliferation, and activated mitogen-activated protein kinase signaling in cardiac fibroblasts. CONCLUSIONS: HMGB1 inhibition could alleviate cardiac fibrosis and remodeling in diabetic cardiomyopathy. Inhibition of HMGB1 might have therapeutic potential in the treatment of the disease.

Protective effects of Salvia plebeia compound homoplantaginin on hepatocyte injury.

Salvia plebeia R. Br is a traditional Chinese herb which has been considered as an inflammatory mediator used for treatment of many infectious diseases including hepatitis. Previously, the compound homoplantaginin was isolated in our group. Hence, we evaluated the protective effects of homoplantaginin on hepatocyte injury. Homoplantaginin displayed an antioxidant property in a cell-free system and showed IC(50) of reduction level of DPPH radical at 0.35 microg/ml. In human hepatocyte HL-7702 cells exposed to H(2)O(2), the addition of 0.1-100 microg/ml of homoplantaginin, which did not have a toxic effect on cell viability, significantly reduced lactate dehydrogenase (LDH) leakage, and increased glutathione (GSH), glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) in supernatant. In vivo assay, we employed the model of Bacillus Calmette-Guérin (BCG)/lipopolysaccharide (LPS)-induced hepatic injury mice to evaluate efficacy of homoplantaginin. Homoplantaginin (25-100mg/kg) significantly reduced the increase in serum alanine aminotranseferase (ALT) and aspartate aminotransferase (AST), decreased the levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1). The same treatment also reduced the content of thiobarbituric acid-reactive substances (TBARS), elevated the levels of GSH, GSH-Px and SOD in hepatic homogenate. The histopathological analysis showed that the grade of liver injury was ameliorated with reduction of inflammatory cells and necrosis of liver cells in homoplantaginin treatment mice. These results suggest that homoplantaginin has a protective and therapeutic effect on hepatocyte injury, which might be associated with its antioxidant properties.